mysql的event schedule 可以让你设置你的mysql数据库再某段时间执行你想要的动作
## Create event ev_t001_user_remain delimiter $$ Create event ev_t001_user_remain on schedule every 1 day starts '2014-07-01 23:00:00' DO Begin TRUNCATE TABLE nowagamedata.t001_user_remain; insert into nowagamedata.t001_user_remain(ur_id,ur_game_id,ur_server_id,ur_platform_id,ur_channel_id,ur_calc_date,ur_user_reg_count,ur_remain_2,ur_remain_3,ur_remain_7,ur_remain_15,ur_create_time) select ur_id,ur_game_id,ur_server_id,ur_platform_id,ur_channel_id,ur_calc_date,ur_user_reg_count,ur_remain_2,ur_remain_3,ur_remain_7,ur_remain_15,date_format(now(),'%Y-%m-%d %H:%i:%s') from meishidata.t001_user_remain; END $$ delimiter ;
引用自 http://blog.sina.com.cn/s/blog_95153c710101fzmn.html
mysql的event schedule 可以让你设置你的mysql数据库再某段时间执行你想要的动作
这与视图是不相同的。
create event test1
on schedule every 1 day
starts '2007-09-01 12:00:00'
on completion not preserve
do insert into yyy values('hhh','uuu');
或
create event test
ON SCHEDULE AT '2007-09-01 12:00:00' + INTERVAL 1 DAY
on completion not preserve
do insert into yyy values('hhh','uuu');
解释:从 2007-09-01开始,每天对表yyy在12:00:00进行一个插入操作。而且只执行一次(on completion not preserve )
使用这个功能之前必须确保event_scheduler已开启,可执行
SET GLOBAL event_scheduler = 1;
或
SET GLOBAL event_scheduler = ON;
来开启(在mysql重启后会失效),也可以直接在启动命令加上“–event_scheduler=1”,例如:
mysqld ... --event_scheduler=1
要使设置永久生效,必须修改/etc/mysql/my.cnf文件:
[mysqld]
添加 event_scheduler=ON
要查看当前是否已开启事件调度器,可执行如下SQL:
SHOW VARIABLES LIKE 'event_scheduler';
或
SELECT @@event_scheduler;
或
SHOW PROCESSLIST;
二、创建事件(CREATE EVENT)
先来看一下它的语法:
CREATE EVENT [IF NOT EXISTS] event_name
ON SCHEDULE schedule
[ON COMPLETION [NOT] PRESERVE]
[ENABLE | DISABLE]
[COMMENT 'comment']
DO sql_statement;
schedule:
AT TIMESTAMP [+ INTERVAL INTERVAL]
| EVERY INTERVAL [STARTS TIMESTAMP] [ENDS TIMESTAMP]
INTERVAL:
quantity {YEAR | QUARTER | MONTH | DAY | HOUR | MINUTE |
WEEK | SECOND | YEAR_MONTH | DAY_HOUR | DAY_MINUTE |
DAY_SECOND | HOUR_MINUTE | HOUR_SECOND | MINUTE_SECOND}
1) 首先来看一个简单的例子来演示每秒插入一条记录到数据表
USE test;
CREATE TABLE aaa (timeline TIMESTAMP);
CREATE EVENT e_test_insert
ON SCHEDULE EVERY 1 SECOND
DO INSERT INTO test.aaa VALUES (CURRENT_TIMESTAMP);
等待3秒钟后,再执行查询看看:
mysql> SELECT * FROM aaa;
+---------------------+
| timeline |
+---------------------+
| 2007-07-18 20:44:26 |
| 2007-07-18 20:44:27 |
| 2007-07-18 20:44:28 |
+---------------------+
2) 5天后清空test表:
CREATE EVENT e_test
ON SCHEDULE AT CURRENT_TIMESTAMP + INTERVAL 5 DAY
DO TRUNCATE TABLE test.aaa;
3) 2007年7月20日12点整清空test表:
CREATE EVENT e_test
ON SCHEDULE AT TIMESTAMP '2007-07-20 12:00:00'
DO TRUNCATE TABLE test.aaa;
4) 每天定时清空test表:
CREATE EVENT e_test
ON SCHEDULE EVERY 1 DAY
DO TRUNCATE TABLE test.aaa;
5) 5天后开启每天定时清空test表:
CREATE EVENT e_test
ON SCHEDULE EVERY 1 DAY
STARTS CURRENT_TIMESTAMP + INTERVAL 5 DAY
DO TRUNCATE TABLE test.aaa;
6) 每天定时清空test表,5天后停止执行:
CREATE EVENT e_test
ON SCHEDULE EVERY 1 DAY
ENDS CURRENT_TIMESTAMP + INTERVAL 5 DAY
DO TRUNCATE TABLE test.aaa;
7) 5天后开启每天定时清空test表,一个月后停止执行:
CREATE EVENT e_test
ON SCHEDULE EVERY 1 DAY
STARTS CURRENT_TIMESTAMP + INTERVAL 5 DAY
ENDS CURRENT_TIMESTAMP + INTERVAL 1 MONTH
DO TRUNCATE TABLE test.aaa;
[ON COMPLETION [NOT] PRESERVE]可以设置这个事件是执行一次还是持久执行,默认为NOT PRESERVE。
8) 每天定时清空test表(只执行一次,任务完成后就终止该事件):
CREATE EVENT e_test
ON SCHEDULE EVERY 1 DAY
ON COMPLETION NOT PRESERVE
DO TRUNCATE TABLE test.aaa;
[ENABLE | DISABLE]可是设置该事件创建后状态是否开启或关闭,默认为ENABLE。
[COMMENT ‘comment’]可以给该事件加上注释。
三、修改事件(ALTER EVENT)
ALTER EVENT event_name
[ON SCHEDULE schedule]
[RENAME TO new_event_name]
[ON COMPLETION [NOT] PRESERVE]
[COMMENT 'comment']
[ENABLE | DISABLE]
[DO sql_statement]
1) 临时关闭事件
ALTER EVENT e_test DISABLE;
2) 开启事件
ALTER EVENT e_test ENABLE;
3) 将每天清空test表改为5天清空一次:
ALTER EVENT e_test
ON SCHEDULE EVERY 5 DAY;
四、删除事件(DROP EVENT)
语法很简单,如下所示:
DROP EVENT [IF EXISTS] event_name
例如删除前面创建的e_test事件
DROP EVENT e_test;
当然前提是这个事件存在,否则会产生ERROR 1513 (HY000): Unknown event错误,因此最好加上IF EXISTS
DROP EVENT IF EXISTS e_test;
mysql的sql代码块中进行变量定义、赋值和使用
## Create event ev_t006 delimiter $$ Create event ev_t01_tmp_ins on schedule every 1 MINUTE DO Begin declare v_name varchar(50); set v_name=concat('tom',round(rand()*10000)); insert into t01_tmp(date_time,name) select date_format(now(),'%Y-%m-%d %H:%i:%s'),v_name; END $$ delimiter ;